3,128 research outputs found

    Particulate organic carbon in agrosystems in the brazilian Semiarid.

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    Drylands cover about 40% of the planet, in which 44% are occupied with cultivated systems. Covering 45% of Brazilian Semiarid the grasslands are main land use this region. In order to increase biomass production and provide food for goats, sheep and bovines are implanted different agrosystems with differences species Cenchurs ciliairis L. (CC), Opuntia ficus indica Mill. (OF), Gliricidia sepium Jacq. (Walp.) (GS), Leucaena leucocephala Lam. De Wit. (LL). However, with removal of native vegetation (NV) there is a change in supply plant material and hence in soil organic matter (SOM), which is formed by substances in different stages of decomposition. Among the chemical components contained in SOM is carbon (C), the main structuring element of nature. In soils, the C can be in the form particulate organic carbon (POC), coming from the biotic residues being quite susceptible to change of land use, and mineral-associated carbon fraction formed by organomineral complexes that are not available to decomposition . POC is associated with the active compartment and can be lost more eas ly, depending on land use. In sense, to evaluate how the introduction of new species for animal feeding can modify the POC, soil samples were collected at following depths: 0-5, 5-10, 10-15, 15-20, 20-30, 30- 40 cm, with four replicates for uses with different ages: NV (always preserved), CC (30 yr), OF (21 yr), GS (17 yr) and LL (24 yr). The air dried soil was separated in a 53 ?m sieve, where the particles larger than >53 ?m corresponded to POC

    Agreement Between the Douleur Neuropathique in 4 Questions and Leeds Assessment of Neuropathic Symptoms and Signs Questionnaires to Classify Neuropathic Pain Among Patients with Leprosy.

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    Neuropathic pain (NP) often occurs during the course of leprosy, and screening tools to differentiate NP from non-NP are often used. However, their performance varies in different settings. The most frequently used scales are the Douleur Neuropathique in 4 questions (DN4) and the Leeds assessment of neuropathic symptoms and signs (LANSS) questionnaires. Thus, we conducted a study to evaluate the agreement between DN4 and LANSS questionnaires to classify NP in 195 leprosy patients attending two reference centers in Sergipe, Brazil. The DN4 and LANSS classified 166 and 110 patients, respectively, as having NP. One hundred and seven (54.8%) were classified as NP by both questionnaires; 59 (30.2%) solely by the DN4 questionnaire and three (1.5%) solely by the LANSS. The agreement of the questionnaires was 66.2% (weak agreement, Kappa = 0.30). Although both questionnaires identified a high proportion of NP, the development of more robust instruments is necessary to ensure the accuracy of diagnosis of leprosy patients classified as having NP

    Solar and biomass hybridization through hydrothermal carbonization

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    Hydrothermal carbonization process can transform wet bio-wastes into value-added products. This work aims to hybridize a concentrating solar technology and a biomass reactor for the continuous and sustainable valorization of biomass. The novel technology proposed integrates a linear beam-down solar field with a twin-screw reactor for continuous HTC process. The solar field consists of two reflections that concentrate linearly the sun energy on the ground, where the twin-screw reactor is placed. A mathematical model is proposed to solve both the heat transfer and HTC kinetics for a co-rotating twin-screw reactor. The incoming heat flux from the solar field (8-20 kW/m(2)), the reactor length (L/D = 30-60 where D is the diameter) and the rotating velocity of the screw (25-100 rpm) are the main variables used to process the biomass up to the desired severity factor. The simulation results of different lignocellulosic biomasses (loblolly pine, sugarcane bagasse, corn stover and rice husk) are validated against literature data. The developed model shows good agreement with experimental results shown in the literature. The proposed technology foresees hydrochar yields of 64-78% for severity factors of 4.2 and 5.3, respectively, in agreement to the experimental results of 63-70% shown in literature. (C) 2021 Elsevier Ltd. All rights reserved

    Efeito de diferentes tipos de cobertura do solo sobre propágulos de fungos micorrizicos arbusculares.

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    O uso de coquetéis vegetais pode beneficiar o sistema solo-planta por aumentar os teores de matéria orgânica e a atividade microbiana. Foi realizado um experimento com objetivo de avaliar o grau de colonização radicular por fungos micorrízicos arbusculares (FMA) dos coquetéis vegetais. O experimento foi conduzido em Petrolina-PE, em um Argissolo com nível alto de P (> 23 mg/dm3), sem adição de fertilizantes e com irrigação. O delineamento experimental foi o de blocos ao acaso, com três tratamentos de cobertura vegetal e três repetições. Os tratamentos foram: T1 ? coquetel vegetal 1, T2 ? coquetel vegetal 2 e T3 ? vegetação espontânea. As espécies de planta utilizadas na cobertura do solo como coquetéis vegetais ou que cresceram como vegetação espontânea apresentaram colonização radicular variando de 55 a 92%. A cobertura do solo com coquetéis vegetais ou pela vegetação espontânea podem promover o aumento da infectividade micorrízica do solo

    Crescimento e esporulação de Alternaria porri, sob diferentes temperaturas.

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    Suplemento. Edição dos Anais do 52 Congresso Brasileiro de Olericultura, Salvador, jul. 2012
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